(P27-050-25) Gastrointestinal Symptoms and Habits Among Pregnant Moms Participating in FeFiFo-MOMS: Effects of Fermented and Fiber-Rich Foods on Maternal and Offspring Microbiome Study

Objectives: To compare effects of fiber and fermented foods on reported gastrointestinal (GI) symptoms and stool habits during pregnancy.

Methods: Pregnant women randomized to one of four arms, including 1) high fiber, 2) high fermented foods, 3) both, or 4) control, completed adapted Gastrointestinal Symptoms Rating Scale, Bristol Stool Scale, and stool frequency survey assessments at baseline (12-22 weeks), 26-30 weeks, and 34-38 weeks of gestation. Paired t-tests and chi square tests compared within group changes at each timepoint.

Results: Of 99 participants (age 35±3 years), the daily number of bowel movements increased in all groups, with strongest shifts from one to two and < 1 to one in the high fermented foods and combined high fermented foods/fiber groups, respectively (all P< 0.001). Stool type shifted from predominantly type 3 reported by 46.9% of the population at baseline to type 4 reported by 44.9% participants at 34-38 weeks (P=0.01 at 26-30 vs 34-38 weeks). These shifts were most present among participants following the high fiber as well as the combined high fermented/fiber diets. Minimal adverse changes were reported in overall GI symptoms only in the high fermented foods group (P < 0.05). At 26-30 weeks, greatest increases in gas, stool frequency, and bloating were experienced by the high fermented foods group, with greatest stool volume increases in the combined diets. Highest increases in stool frequency, stool volume, and bloating were maintained in the high fermented foods group at 34-38 weeks.

Conclusions: Among women during pregnancy, both fiber and fermented foods may increase frequency of bowel movements. High fiber foods led to the greatest shifts in stool type to a softer, smoother form, while GI symptoms may be more prevalent and consistent with high presence of fermented foods. Inclusion of fiber and fermented foods during pregnancy may have useful implications for GI symptoms and stool habits.

Funding Sources: This research was made possible by the National Heart, Lung, and Blood Institute and philanthropic donation from Laura and Michael Paulus.